Lake olive duns are found on most ponds, lakes and reservoirs but really large hatches are mainy seen on clean, natural lakes. There are a number of different species but all the duns are very similar. They tend to be dull browns and olives, which means the generic patterns are suitable for most waters.
On damp or humid days it can take a long time for the duns to leave the water’s surface. This can cause a feeding frenzy in the trout and it pays to watch for localised hatches in these conditions. There are two distinct hatch periods in the year. One in May/June and another in September/October. Recent warm years have seen these two periods move to earlier and later in the year.
Smaller is better with these flies. If you are not having any luck, and there appears to be a hatch on, a smaller pattern can often change a fisherman’s fortunes.

River Fishing
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CDC Dun
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Gold Ribbed Hare’s Ear
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Olive Dun
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| Size 12-14 | Size 14 only | Size 14 only |
| The CDC Dun is a representation of a lake olive dun. There are many different species of lake olive and the similar pond olive but the dun stage of all is very similar. There are two distinct hatch periods in the year: March-June and September-October. During these periods they are prolific all day long but dampness makes flying difficult – great for the trout! | The Gold Ribbed Hare’s Ear represents a lake olive dun. They hatch from early spring through to the autumn with peaks in May and September. This is a famous pattern that has killed a good many trout in its time. The Gold Ribbed Hare’s Ear should be an essential pattern in every fly fisherman’s tackle bag. Don’t leave home without it! | The Olive Dun is a generic lake olive pattern. It can be fished effectively on lakes throughout the season but is most effective in the late Spring and late Summer peaks. Like the other lake olive dun patterns, delicate casts are required as the flies only appear in large numbers when conditions are still. Short delicate casts are most effective. |
| River - No
Lake - Yes Time of Year - All Weather/Time – Damp, Drizzle, Humid |
River - No
Lake - Yes Time of Year - All Weather/Time – Damp, Drizzle, Humid |
River - No
Lake - Yes Time of Year - All Weather/Time – Damp, Drizzle, Humid |



